1. Field of the Invention
The present invention relates to a feed limiting device and a control device and, more particularly, to a feed limiting device for limiting feed (i.e., electrical feed) to electrical components (such as head lamps, an air conditioner and an audio system) mounted on a vehicle in an economy running state and a control device.
2. Description of the Relevant Art
Hitherto, in order to meet the requirement of conservation of natural resources, various kinds of techniques whereby fuel efficiency of a vehicle is improved have been proposed, and have been commercially practical. For example, there is a function (so-called economy running function) whereby an engine is automatically stopped when a vehicle is stopped at an intersection or the like, and then, the engine is automatically started when a driver's foot is taken off a brake pedal, resulting in a reduction in fuel consumption during a stop.
When the speed is 0 km/h and the brake pedal is held down, it is judged determined that an engine automatic stop condition has been satisfied and the engine is automatically stopped, leading to the economy running state. The engine automatic stop condition is not limited to that. For example, a condition that a gear is in a neutral position is sometimes added to the condition that the speed is 0 km/h and the brake pedal is held down.
When the driver's foot was taken off the brake pedal in the economy running state and therefore, the engine automatic start condition became satisfied, the engine was automatically started. Here, the engine automatic start condition is not limited to that. A condition that a gear is operated is sometimes added to the condition that the brake pedal is not held down.
By the way, since an alternator whose drive source is the engine does not generate electric power in the economy running state, a power supply to electrical components mounted on the vehicle is conducted only with electric power from a battery. If this situation is continued for a long period, there is a risk that the battery may be excessively consumed and that the battery degradation speed may become higher.
In order to solve this problem, various techniques have been proposed. For example, the below-mentioned Patent Document 1 discloses a technique, wherein when a vehicle is turned to an economy running state, feed to head lamps, an air conditioner and an audio system are forcefully cut off so as to reduce a load on a battery. The Patent Document 2 discloses a technique, wherein when a vehicle is in an economy running state, a situation where there is a large difference between a pre-selected temperature of an air conditioner and an actual ambient temperature is changed to a situation where there is a small difference therebetween so as to reduce a load on a battery.
However, in the technique disclosed in the Patent Document 1, when the vehicle is turned to the economy running state, the feed to the head lamps, the air conditioner and the audio system are forcefully cut off without consideration of a user's intention or an external environment. As a result, there is a risk that an event where feed is cut off with undesired timing may be caused, leading to user discomfort. In the technique disclosed in the Patent Document 2, feed is not cut off, but there is a risk that processing for reducing a load on the battery may be conducted with undesired timing, leading to user discomfort.
[Patent Document 1] Japanese Patent Application Laid-Open Publication No. 2001-341596
[Patent Document 2] Japanese Patent Application Laid-Open Publication No. 2002-331825